Derivative Instruments and Hedging Activities (Intro) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014 MW	Mar. 31, 2013	Dec. 31, 2013
Master Netting Arrangements Numeric [Line Items]
Obligation to return cash collateral obligation under master netting arrangement	$ 10		$ 9
Cash collateral posted under master netting arrangements	21		22
Commodity Price Risk Nontrading [Line Items]
Baseload generation fleet capacity (in MW)	7,369
Intermediate and peaking generation fleet capacity (in MW)	3,309
Commodity Price Risk (Non-trading) - Cash Flow Hedges (Numeric) [Abstract]
Net unrealized after-tax gains (losses) expected to be reclassified into earnings within 12 months related to commodity price risk cash flow hedge contracts	24
No or insignificant amounts previously recorded in AOCI reclassified to earnings related to commodity price risk cash flow hedge contracts	no such reclassifications	no such classification
No or immaterial hedge ineffectiveness related to commodity price risk cash flow hedge contracts	no hedge ineffectiveness	no hedge ineffectiveness
Commodity Price Risk (Non-trading) - Economic Activity (Numeric) [Abstract]
Year of expiration of the maximum maturity date of economic activity derivative contracts	2019
Unregulated Retail Energy [Member]
Pre-tax Gains (Losses) of Economic Activity - Unregulated Business (Details) [Abstract]
Pre-tax gain (loss)	(26)	(8)
Unregulated Wholesale Energy [Member]
Pre-tax Gains (Losses) of Economic Activity - Unregulated Business (Details) [Abstract]
Pre-tax gain (loss)	(789)	(822)
Fuel [Member]
Pre-tax Gains (Losses) of Economic Activity - Unregulated Business (Details) [Abstract]
Pre-tax gain (loss)	(1)	(1)
Energy Purchases [Member]
Pre-tax Gains (Losses) of Economic Activity - Unregulated Business (Details) [Abstract]
Pre-tax gain (loss)	580	634
PPL Energy Supply LLC [Member]
Master Netting Arrangements Numeric [Line Items]
Obligation to return cash collateral obligation under master netting arrangement	10		9
Commodity Price Risk Nontrading [Line Items]
Baseload generation fleet capacity (in MW)	7,369
Intermediate and peaking generation fleet capacity (in MW)	3,309
Commodity Price Risk (Non-trading) - Cash Flow Hedges (Numeric) [Abstract]
Net unrealized after-tax gains (losses) expected to be reclassified into earnings within 12 months related to commodity price risk cash flow hedge contracts	24
No or insignificant amounts previously recorded in AOCI reclassified to earnings related to commodity price risk cash flow hedge contracts	no such reclassifications	no such classification
No or immaterial hedge ineffectiveness related to commodity price risk cash flow hedge contracts	no hedge ineffectiveness	no hedge ineffectiveness
Commodity Price Risk (Non-trading) - Economic Activity (Numeric) [Abstract]
Year of expiration of the maximum maturity date of economic activity derivative contracts	2019
PPL Energy Supply LLC [Member] | Unregulated Retail Energy [Member]
Pre-tax Gains (Losses) of Economic Activity - Unregulated Business (Details) [Abstract]
Pre-tax gain (loss)	(26)	(8)
PPL Energy Supply LLC [Member] | Unregulated Wholesale Energy [Member]
Pre-tax Gains (Losses) of Economic Activity - Unregulated Business (Details) [Abstract]
Pre-tax gain (loss)	(789)	(822)
PPL Energy Supply LLC [Member] | Fuel [Member]
Pre-tax Gains (Losses) of Economic Activity - Unregulated Business (Details) [Abstract]
Pre-tax gain (loss)	(1)	(1)
PPL Energy Supply LLC [Member] | Energy Purchases [Member]
Pre-tax Gains (Losses) of Economic Activity - Unregulated Business (Details) [Abstract]
Pre-tax gain (loss)	580	634
LG And E And KU Energy LLC [Member]
Master Netting Arrangements Numeric [Line Items]
Cash collateral posted under master netting arrangements	21		22
Louisville Gas And Electric Co [Member]
Master Netting Arrangements Numeric [Line Items]
Cash collateral posted under master netting arrangements	$ 21		$ 22